For that work, Varshney studied six cities in India – three in which Hindus and Muslims had frequent riots, with many lives lost, and three in which rioting was rare despite similar religious demographics.

He credited the different outcomes in peaceful cities to long-standing relationships between Hindus and Muslims either at the neighborhood level or – more important – at the organizational level of business associations, student unions, trade unions, and other groups.

Where such relationships existed, the Indian cities studied were able to manage tensions, he said. No matter the country or the religion, “if you have prior relationships existing in routine normal life, in schools, in businesses, etc., professions – a very demonstrable and positive effect is maintenance of peace during times of tension,” Varshney said. He stressed that such integration should be at the day-to-day level; specific interfaith dialogues based on religion do not produce as strong a foundation for peace as routine integration.

On the other hand, “it is much harder to create integration during times of tension,” he said.